Not all tests are created equal! Modifiers are adjustments made to a test’s target number (not the roll itself ), that make the test easier or harder for a character to pass. Bonuses are modifiers that increase the target number and thus make success more likely, while Penalties are modifiers that decrease the target number and thus make success less likely. If a test would be subject to more than one modifier, simply add their values together to determine the net modifier for that test.